Ignoring that this is merely your opinion and hardly a fact, what are these exclusives you speak of? (And PS3 has a lot more exclusives than just MGS4 & VF5)

Mass Effect, Halo 2, Phantasy Star Universe(not coming to any other next gen console) and Gears of war. I am sure Final Fantasy 13 will make its way to 360 also, Final Fantasy series has already debuted on 360 with Final fantasy 11.